Method and apparatus for operating the ram of an impact machine



AKIRA ASARI Feb. 18, 1969 METHOD AND APPARATUS FOR OPERATING THE RAM OFAN IMPACT MACHINE Sheet Filed July 12. 1966 Fig INVENTOR.

BYMLMMKZ MM Feb. 18, 1969 I AKIRA ASARI 3,427,357

METHOD AND APPARATUS FOR OPERATING THE RAM OF AN IMPACT MACHINE FiledJuly 12, 1966 Sheet 2 of 2 14 ll '2 1e l3 l5 l8 I? I II l3 3 UnitedStates Patent 40/ 45,744 US. Cl. 72-453 Int. Cl. B213 9/18, 7/36; G01n3/62 2 Claims ABSTRACT OF THE DISCLOSURE A method for raising a ram inan impact processing machine. Two pairs of jack assemblies which aremovable between an uppermost ram supporting position and a lowermost ramsupporting position are provided. Each of them has vertically movablejack members and associated ram support members. The first pair of jackassemblies supports the ram in the raised position at the start of theoperation, and the ram support members are retracted to allow the ram todescend. The second pair of jack members raises the ram while the firstpair of jack members descends. The ram is again released, andsubsequently raised by the first pair of jack members while the secondpair descends.

The present invention relates to an improved impact processing methodand apparatus which utilizes a fiuid at a high pressure as its drivingforce supply source, and more particularly to a novel method foroperating the ram in the above-type of impact processing machine and anovel device for carrying out the method.

Generally, in an impact processing machine the ram for the processingmachine is operatively disposed within the body of the machine so thatprior to actuation for one cycle of the impact processing operation, theram is held in its uppermost inoperative position in the machine bodyand then the ram is caused to rapidly descend downwardly toward a workpiece positioned on an anvil in the lower portion of the machine body soas to perform a desired impact processing operation on the work piece,and thereafter, the ram is caused to move upwardly to its initialuppermost inoperative position and held there ready for the next cycleof operation. In such a type of impact processing machine, in order toraise the descended ram to its initial inoperative position after theram has performed the desired processing operation on the work piece, ajack device is usually employed. The jack device may be operated byeither hydraulic pressure or mechanical means such as a crank. In oneconventional type of jack device employed for the purpose, thevertically movable operating member of the jack device maintains itsfully extended position so long as the operating member upholds the ramin its inoperative position and the operating member must be caused todescend just before the ram is actuated or caused to descend rapidly toperform a desired impact processing operation on a work piece positionedbelow the ram so that the operating member will not impede the descentof the ram. However, the operating member of the jack device usuallytakes a rather long time to descend, as much as one half of the timerequired for one cycle of the processing operation by the ram whichimpedes improvement of the impact processing operation in the prior artimpact processing machine.

One object of the present invention is to provide an improved impactprocessing method which can effec- 3,427,857 Patented Feb. 18, 1969tively eliminate the above defects inherent in the prior art impactprocessing methods and machines and also to provide an improved machinefor carrying out such an improved method.

Another object of the present invention is to provide an improved impactprocessing method which can positively eliminate the time required forthe operating members of a jack device to descend from the total timerequired for one cycle of impact processing operation so that thedescending time of the operating members does not constitute a part ofthe total time required for one cycle of the impact processing operationthereby to substantially shorten the total time required for one cycleof the impact processing operation.

According to the present invention, in order to operate the ram in animpact processing machine, at least two pairs of jack assemblies areprovided each of which generally comprises a pair of vertically movablemembers and their associated vertically and laterally movable ramsupport members adapted to support and release the ram. The pairs ofjack assemblies are adapted to alternately support and release the ramin such a manner that prior to actuation of the ram one pair of jackassemblies will maintain the ram in its uppermost inoperative positionwhile the other pair of jack assemblies remain in their lowermostposition apart from the ram when the ram is to be actuated for itsintended impact processing operation, the vertically and laterallymovable members associated with the first pair of vertically movablemembers which now support the ram are pulled away from the ram withtheir as sociated vertically movable members maintaining their uppermostposition so as to release the ram to allow the latter to descendrapidly, and after the completion of one cycle of impact processingoperation, the second pair of vertically movable members, which are nowin their lowermost positions, are caused to move upwardly and at thesame time the associated vertically and laterally movable members arecaused to advance so as to engage and support the ram. In this case thefirst pair of vertically movable members and their associated verticallyand laterally movable members are caused to descend with the lattermembers pulled back as the second pair of vertically movable members andtheir laterally movable members are moving upwardly whereby the ram canbe operated by the alternating action of the two pairs of jackassemblies.

According to the present invention, there is also provided an improvedram operating device for an impact processing machine which comprisesat. least two pairs of jack assemblies each pair of which is adapted tomove independently of the other pair. The device includes a pair of jackmembers and a pair of retractive members respectively associated withsaid jack members for movement together with the associated jack membersand also for movement toward and away from the ram independently of themovement of the associated jack members, the retractive members being soarranged that when these members are advanced they can support the ramand when they are retracted they can release the ram so as to allow theram to descend rapidly in order to perform a desired impact processingoperation.

The above and other objects and advantages of the present invention willbe more readily apparent from the following description when read inconnection with the accompanying drawings in which:

FIG. 1 is a vertical sectional view of an impact processing machineincorporating a preferred form of device for operating the ram in saidprocessing machine in which the novel method of the present inventioncan be successfully carried out;

FIG. 2 is a cross-sectional view taken along the line IIII of FIG. 1;and FIGS. 3A and 3B are explanatory views for diagrammatically showingvarious stages in an impact processing operation cycle to be performedby a prior art method and the novel method.

The present invention will now be explained referring to theaccompanying drawings, and especially to FIG. 1 thereof in which animpact processing machine which incorporates a preferred form of noveldevice for operating the ram in the processing machine is illustrated.The impact processing machine generally comprises a main body whichconsists of three vertically connected hollow portions, that is, theuppermost portion 1, intermediate portion 1 and lowermost portion 1".The uppermost portion 1 defines a gas cylinder into which a gas under ahigh pressure is to be introduced and entrapped and a trigger chamber 3is formed in the top wall of the gas cylinder 1. The top wall of theuppermost body portion or gas cylinder 1 is further provided with a gaspassage 19 which connects the interior of the trigger chamber 3 and agas flow conduit 20 which leads to a suitable conventional pressurizedgas supply source (not shown). A ram 4 having a plunger 2 on the top isoperatively disposed within the main body of the processing machine andextends from the gas cylinder 1 through the bottom wall of the cylinderinto the intermediate body portion 1. When the ram 4 is not operated,the plunger 2 of the ram 4 is positioned within the trigger chamber 3 ofthe gas cylinder 1 while the lower enlarged end of the ram 4 ispositioned apart from the bottom wall of the gas cylinder 1 as seen inFIG. 1. The position of the ram 4 shown in FIG. 1 is the initialposition or dead point of the ram 4 prior to the start of an impactprocessing operation.

For the operation of the ram 4, a change-over valve 6 disposed in theconduit 20 is initially shifted to its partially open position so as topermit a restricted flow of high pressure gas to flow from the supplysource through the conduit 20 and gas passage 19 into the triggerchamber 3. The thus introduced restricted flow of pressurized gas actsagainst the upper surface of the plunger 2 thereby causing ram 4 todescend within the main body a distance just enough to allow the plunger2 of the ram to clear the trigger chamber 3. As soon as the plunger 2has cleared the trigger chamber 3, the change-over valve 6 is shifted toits fully open position so as to permit a nonrestricted flow of highpressure gas to pass into the trigger chamber 3 which acts against theupper surface of the plunger 2 with a stronger force so that the ram 4will descend rapidly to strike against a work piece (not shown) disposedon an anvil 21 which is in turn provided on a block member 22 which iselastically supported by shock absorbing elements or springs 23 whichare disposed between the under surface of the block and the innersurface of the bottom of the lowermost body portion 1".

After the completion of one cycle of the impact processing operation, itis necessary to move the ram 4 upwardly to return it to its initialposition in which the plunger 2 of the ram 4 is disposed within thetrigger chamber 3 formed in the top wall of the gas cylinder 1.According to the present invention, a novel jack device is provided foroperating the ram 4. The novel jack device comprises two pairs of jackassemblies. One jack assembly generally comprises a pair of oil pressureoperated pistons 7 and 7 (only one of them is shown in FIG. 1) and theirassociated pair of cylinders '9 and 9 (only one of them is shown inFIG. 1) while the other jack assembly generally comprises a pair of oilpressureoperated pistons 8 and 8 and their associated pair of cylindersand 10. The cylinders 9, 9 and 10, 10 are respectively formed in theblock member 22 adjacent to the four corners of the block member andcommunicate through bores formed in the top wall of the block member 22and in the bottom wall of the intermediate body portion 1' which alsohas vertical openings 24, 24 and 25, 25 adjacent to the four corners ofthe intermediate body portion 1 in positions corresponding to the fourcylinders 9, 9 and 10, 10 respectively. Thus, the four pistons 7, 7 and8, 8 can move upwardly and downwardly within their respectivelyassociative cylinders 9, 9 and 10, 10 and 24, 24 and 25, 25. The blockmember 22 is also provided with oil passages 26, 27, 28 and 29 whichcommunicate through oil conduits 30, 31, 32 and 33 to suitable oilpressure supply sources (not shown). The passages 26 and 27 communicatewith one pair of cylinders 9 and 9 so as to operate the pistons 7 and 7disposed in the cylinders while the passages 28 and 29 communicate withthe cylinders 10 and 10 so as to operate the pistons 8 and 8. In theillustrated embodiment of the jack device, in each pair of assembly thejack pistons are diametrically opposed to each other with respect to thecenter ram 4 and the jack cylinders are also diametrically opposed toeach other with respect to the center ram 4. The openings 24, 24 and 25,25 formed adjacent to the four corners of the intermediate body portion1' extend vertically along a substantial length of the body portion andopen to both the interior and exterior of the intermediate body portion1'. The oil pressure-operated pistons 7, 7 and 8, 8 are respectivelyprovided at their upper ends with pawl boxes 11, 11 and 12, 12,respectively, and inclined cylindrical pawls 13, 13 and 14, 14 extendacross the respectively associated pawl boxes 11, 11 and 12, 12 forfreely slidable movement within the inclined bores formed in theassociated pawl boxes in advancing and retreating directions. Pistons15, 15 and 16, 16 are respectively provided in the bores of the pawls13, 13 and 14, 14 for operating the pawls and the pistons are adapted tomove into and out of the bores of the respectively associatedcylindrical pawls so as to effect reciprocal movement of the pawls inadvancing and retreating directions. The pistons 15, 15 and 16, 16 areoperatively connected to the respective pawl boxes by means of supportplates 17, 17 and 18, 18. The pawls 13, 13 and 14, 14 are so arrangedthat when the pawls are fully advanced into the interior of theintermediate body portion 1' they can engage the lower edge of the ram 4at diagonal opposed points thereof, while when they are fully retreatedinto the pawl boxes they move out of engagement with the ram edgeportions. It should be understood that the two pawls in the same pairare caused to advance and retreat simultaneously; that is, the two pawlsand associated pistons should move always in the same direction. Foreffecting the forward and backward movement of the pistons 15, 15 and16, 16, and accordingly, the pawls 13, 13 and 14, 14, separate oilpressure conduits are provided for each piston and pawl assembly (onlythose associated with two of such assemblies are schematically shown inFIG. 1). In order to advance each pawl, oil pressure is supplied from asuitable oil supply source (not shown) via an associated conduit andbore formed in the associated pawl box and pawl against the rear surfaceof the piston head within the particular pawl while in order to retractthe thus advanced pawl oil pressure from the same supply source issupplied via another associated conduit and another bore formed in thesame associated pawl box and pawl at points apart from the previouslymentioned bores in the same pawl box and pawl against the front surfaceof the same piston head. The shifting of the oil pressure flow from oneconduit to the other conduit is effected by means of a changeover valvecommon to the two oil pressure conduits. In order to move upwardly anddownwardly, each jack piston, as mentioned above, two separate passagesare provided for each jack piston in the block member 22 and the twopassages communicate with the respective oil pressure conduits which inturn communicate with a common oil pressure supply source.

The pairs of oil pressure-operated jack pistons 7, 7 and 8, 8 are soarranged and operated that when the ram 4 is to be positioned in itsuppermost or inoperative position, one pair of jack pistons of the twopairs of pistons, for example, the jack pistons 7 in the same pair areurged upwardly by supplying oil pressure from the oil supply sourcethrough the conduits 30 and passages 26 into the cylinders 9 and at thesame time their associated pawls 13 are urged forwardly into theinterior of the intermediate body portion 1' by supplying oil pressureagainst the rear surface of the associated pistons 15 in the manner asmentioned above so as to abut against the lower edge of the ram head attwo diagonally opposite corners of the latter. Thus the ram 4 will bepushed upwardly to its inoperative uppermost position being supported bythe abutting pawls 13 which are urged upwardly as the associated jackpistons 7 ascend within the cylinders 9 and openings 24 and the ram 4will be held in the uppermost position by the fully advanced pawls 13when the jack pistons 7 have reached the uppermost position. In thiscase, the jack pistons 8 remain in their lowermost position and theirassociated pawls 14 also maintaining their fully retracted position. Inorder to effect the actuation of the ram 4 from the above-mentionedinoperative position, firstly, the pawls 13 associated with the jackpistons 7 are retracted from their advanced position by supplying oilpressure against the front surface of the pistons 15 and in this casethe pawls will release the ram 4. However, the ram 4 does notimmediately descend, but remains suspended within the machine bodybecause of the high pressure gas entrapped within the cylinder 1 whichacts against the lower surface of the plunger 2 of the ram 4 so as tohold the ram in position. After the pawls 13 are completely retractedfrom the interior of the body portion 1, the change-over valve -6 isshifted as described above to cause the ram to descend to carry out thedesired impact process by the impact of the descending ram 4. After onecycle of the impact processing operation by the ram 4 has beencompleted, the jack pistons 8 in the other pair which are now in theirlowermost positions are caused to ascend and at the same time theirassociated pawls 14 are caused to advance to engage the ram 4 in themanner as described above. The jack pistons 8 continue to ascend withtheir associated pawls 14 abutting against the underside of the ram attwo diagonally opposite corners of the latter until the ram reaches itsuppermost inoperative position where the ram is maintained ready foranother cycle of impact processing operation. The pistons 7 which havepreviously been raised to the uppermost position and held there, are nowcaused to descend by supplying oil pressure from the supply sourcethrough the conduit 31 and passage 27 into the upper portion of thecylinders 9 and their associated pawls 13 are simultaneously retractedwhile the other pair of jack pistons 8 are ascending and theirassociated pawls 14 are advancing. After the jack pistons 7 have reachedtheir lowermost position and the jack pistons 8 have reached theiruppermost position, and in consequence the ram 4 has been returned toits upper-most position, ram 4 is ready for the next cycle of impactprocessing operation by repeating the operation described above.

The impact processing cycle carried out by the use of the illustratedimpact processing machine incorporating the novel dual-type jack deviceaccording to the present invention is diagrammatically shown in FIG. 3Band that by the use of one conventional impact processing machineincorporating a prior art single-type jack device is diagrammaticallyshown in FIG. 3A. When the cycle of FIG. 3B is compared with that ofFIG. 3A, it will be noted that the total time required for performingone cycle of impact processing operation by the machine incorporatingthe novel dual-type jack device is shorter than that required for thesame operation by the conventional machine incorporating the prior artsingle-type jack device by an amount substantially corresponding to thetime required for the jack pistons to descend. In these figures, varioussymbols designate the following motions:

JU-Upward movement of jack pistons JD-Downward movement of jack pistonsW-Impact stroke (downward movement of ram) VOOpening of change-overvalve 6 VCClosing of change-over valve 6 PA-Advancement of pawlsPRRetreat of pawls As mentioned hereinabove, in the novel dual-type jackdevice according to the present invention, since the two pairs of jackassemblies are adapted to alternately return the ram to its uppermostposition and when the ram is to be actuated the supporting members orpawls associated with the respective jack pistons. are caused to retreatso as to release the ram, the time required for the jack pistons todescend will not be added to the total time required for one cycle ofthe impact processing operation and accordingly, as compared with anyconventional operation the total time required for performing onecomplete cycle of impact processing operation will be shortened by anextent corresponding to the time required for the jack pistons todescend, and furthermore, immediately after a work piece has beenpositioned on the anvil, the ram can be actuated, and accordingly, ifthe work piece is hot, the same can be properly impactprocessed beforethe same becomes cold.

It should be understood that the present invention is not preciselylimited to the illustrated construction and arrangement, but theinvention can be equally applied to other constructions and arrangementsin which the jack pistons and the associated pawls are actuated bymechanical means rather than hydraulic pressure as illustrated.Furthermore, the construction of and arrangement of the jack pistons andtheir associated pawls may vary within a Wide range within the scope ofthe present invention; for example, the jack piston rods themselves mayserve as lthe support means for the ram and rock laterally thereby toeliminate their associated pawls which are otherwise necessary.

While one preferred embodiment of the invention has been shown anddescribed in detail it will be understood that the same is for thepurpose of illustration only and is not to be taken as a definition ofthe scope of the invention, reference being bad for this purpose to theappended claims.

What is claimed is:

1. A method for raising a ram in an impact processing machine by the useof a jack device having at least two pairs of jack assemblies movablebetween an uppermost ram supporting position and a lowermost non-ramsupporting position and each of which includes vertically movable jackmembers and associated ram support members movable together with saidrespective jack members movable laterally in advancing and retreatingdirections for supporting and releasing said ram independently of thejack members, said method comprising the steps of retracting the ramsupport members of the first pair of jack assemblies which are in theiruppermost ram supporting position while associated jack members remainin their uppermost position so as to release the ram to allow the sameto descend rapidly to complete its downward stroke to accomplish adesired impact processing operation on a Work piece, then advancing theram support members of the second pair of jack assemblies which are inthe lowermost position so as to support said ram, and at the same timecausing the jack members of the second pair to ascend to return the ramto its initial uppermost position while being supported by the supportmembers of the second pair of jack members while at the same timecausing said jack members and the associated support members of thefirst pair of jack assemblies to descend, repeating the cycle ofoperations by raising the jack members of the first pair while loweringthe jack members of the second pair.

2. A device for operating the ram in an impact processing machinecomprising at least two pairs of jack assemblies adapted to be operatedindependently of each other, and means for alternately actuating thejack assemblies of said pair of the jack assemblies for causing one jackassembly to lift the ram and simultaneously causing the other jackassembly to descend, each pair of said jack assemblies including a pairof vertically movable jack members and a pair of associated ram supportmembers for vertical movement together With said jack members and alsofor lateral movement in advancing and retreating directions so as tosupport and release said ram independently of the jack members, said ramsupport members being adapted to advance to support the ram when the ramis to be caused to ascend and to retract from the advanced position torelease the ram when the ram is to be actuated in order to perform adesired impact processing operation.

References Cited UNITED STATES PATENTS CHARLES W. LANHAM, PrimaryExaminer.

G. P. CROSBY, Assistant Examiner.

US. Cl. X.R. 72-437

